Stabilised antacid compositions

An aqueous antacid suspension comprises aluminium and magnesium hydroxides and from 0.5 to 2.0% by wt. of a stabilising additive comprising an alkali metal and / or an alkaline earth metal gluconate. Sodium, potassium, calcium, and magnesium gluconates are exemplified. The invention also comprises anhydrous antacid compositions comprising from 4 to 8 pts. by wt. Al(OH)3, 1 to 8 pts. by wt. Mg(OH)2 and from 0.5 to 2.0 pts. by wt. of Na, K, Ca, or Mg gluconate. Magnesium gluconate may be formed in situ in the aqueous suspension of Al(OH)3 and Mg(OH)2 by addition of gluconic acid or glucono-delta-lactone. Conventional excipients may be added to the aqueous antacid suspensions. The latter may be used in combination with anti-flatulents such as methylpolysiloxane, local anaesthetics such as lidocaine, antibiotics such as tetracycline hydrochloride or penicillin, sedatives such as phenobarbital, tranquilizers such as reserpine or meprobamate, antispasmodics such as aminopentamide or belladonna alkaloids, protective coating agents such as Al(OH)3 gel or magnesium trisilicate, or an alkalisoluble hydrophilic colloid, e.g. carboxymethyl cellulose, alginates, carboxypolymethylene or cellulose acetate phthalate. The anhydrous composition may be tabletted, encapsulated in gelatin, or resuspended in water. The composition may be formulated with an analgesic, e.g. aspirin or acetyl p-aminophenol, into an effervescent or conventional tablet.